A heating pump is a pump with a build-in heater to heat liquid being pumped. An existing heating pump includes a housing, an impeller received in the housing, a motor to drive the impeller and a heater fixed to an interior surface of the housing. In operation, liquid entering the housing via an inlet, is forced against the heater by the impeller and finally expelled through an outlet of the housing. In this process, the liquid is heated as it contacts the heater and therefore leaves the pump with an elevated temperature. However, only the heat from the inner surface of the heating tube is absorbed by the liquid, the heat radiating from the outer surface is wasted. This results in a heating pump with a low heating efficiency.
The present invention aims to provide a new heating pump which can solve or at least mitigate the above mentioned problem.